I have a Rhapsody subscription and an unlimited* data plan from ATT. I can browse Rhapsody's website, but much of it is in Flash. If my browser supported flash, then I could login and stream music on demand to my BB Bold.

Any chance of this?

The closest that I've found so far is that Opera's website says about the Opera Mobile 9.5 (BETA) browser "Known Issues... ActiveX is disabled — Flash plugins and embedded video streaming do not work." This suggests to me that the final (non-beta) version of Opera Mobile 9.5 will support flash. So maybe someday...